Thick smoke billowed from the gulch and turned the sun crimson red. By 3 p.m., about 10 acres had burned, but fire officials said many more acres of brush were on fire.

The fire appeared to have started near the Mililani Agricultural Park in the gulch, said fire spokesman Capt. Emmit Kane. The gulch is lined by old Navy facilities that are now used for storage.

A large car lot with hundreds of new cars sits in the gulch, but the fire did not threaten the vehicles.

The fire department's Air One helicopter was joined by a military Chinook helicopter to make water drops on the fire.

Kane said much of the brush that is burning is former sugar cane land that was "allowed to grow wild" and fueled the fire.

"Where suburbia meets wild land, there will always be that problem," Kane said.